Tamping machine for packing ballast under railroad ties



June 11, 1963 E. FL EING 3,093,089

TAMPING MACHINE FOR PACKING BALLAST UNDER RAILROAD TIES Filed July 5, 1956 4 Sheets-Sheet l '3 Q: g X] INVENI'OP ERIK/l FL E/M 70 RNEyS June 11, 1963 Filed July 5, 1956 FIG. 2

E- F LEING TAMPING MACHINE FOR PACKING BALLAST UNDER RAILROAD TIES 4 Sheets-Sheet 2 \III II II II Ii llllll June 11, 1963 E. FLEING 3,093,089

TAMPING MACHINE FOR PACKING BALLAST UNDER RAILROAD TIES Filed July 5, 1956 4 Sheets-Sheet 5 FIG. 4

- I awe-Mm ERICH Elf/I6 June 11, 1963 E. FLEING 3,093,089

TAMPING MACHINE FOR PACKING BALLAST UNDER RAILROAD TIES Filed July 5, 1956 4 Sheets-Sheet 4 wrs/vme E R IC H FLEl/VG 1w Mays United States Patent 3,093 089 TAMPING MACHmE FGR PACKING BALLAT 1 UNDER RAILRGAD TIES Erich Fleing, Niedersprockhoevel, Westphalia, Germany,

assignor to Friilich & Kliipfel, Wuppertal-Barmen, Germany, a corporation of Germany Filed July 5, 1956, Ser. No. 595,926

' 3 Claims. (Cl. 10414) This invention relates to a tamping machine, and more particularly to a manually guided tamping machine for packing ballast under railroad ties.

In the laying and maintenance of railroad tracks, it is necessary to tamp or pack the ballast which generally consists of broken stone under the railroad ties. For this purpose, so-called tamping picks or hammers were used with which the operator would manually compact the broken stone ballast under the tie until the same appeared' to be sufiiciently firm. This manual operation, however, is very time consuming and expensive from a labor standpoint and did not result in a uniform and satisfactory packing of the ballast.

More recently there have been developed automatic tamping machines which are mounted on a railroad car and which force the ballast below the ties by means of rapidly operated hammer-like tamping tools. The use of these automatic tamping machines, which have been designated rail-tamping machines, however, involved certain disadvantages as the same were relatively expensive and would tie up the track when in use.

While manually guided, power-driven tamping tools have been proposed, the same are not completely satisfactory in operation since a considerable amount of recoil occurred during their operation which had to be absorbed by the operator and which would frequently lead to injury. Furthermore, with these prior known tamping tools, the materials to be compacted was solely subjected to impact forces in a single direction so that the same could escape toward the outside which did not produce entirely satisfactory or uniform results.

One object of this invention is a power-driven, manually guided tamping tool which is simpler in construction, maintenance and manufacture than the previously known tools and which overcomes the above mentioned disadvantages. This, and still furthe robjects, will become apparent from the following description read in conjunction with the drawings in which:

FIGURE 1 is a diagrammatic side elevation showing an embodiment of a tamping tool in accordance with the invention in operating position,

FIGURE 2 is a side elevation of the tamping head of the tamping tool of FIGURE 1,

FIGURE 3 is a plan view of the tamping head shown in FIGURE 2,

FIGURE 4 is a plan view, partially in section, of the cylinder head of the device of FIGURE 1, and,

FIGURE 5 is a plan view of a further embodiment of a tamping head for a tamping tool in accordance with the invention.

FIGURE 5a shows a force vector diagram of the tamping head operation.

The power-driven tamping tool, in accordance with the invention, for compacting ballast under railroad ties comprises at least two tamping heads mounted side-byside for limited reciprocating motion in a forward and rearward direction, and means are provided for alternately driving said heads in a forward direction. The heads are preferably mounted in manual holding means for manual manipulation and guidance.

The alternately driven side-by-side tamping heads allow a substantial increase in the efficiency of the device ice producing a much better compacting eflect and additionally causes a substantial reduction in the recoil eflect, allowing the tool to be handled much more easily and without danger.

In accordance with a preferred embodiment of the invention, the leading edges of the tamping heads with which the compacting is eifected are so shaped that upon being driven forward they not only exert a force on the ballast being compacted in that direction but also effect a sideward force on the ballast in the direction of the other tamping head. This may be effected, for example, by having the leading edges of the tamping heads, which may be straight or curved, inclined toward each other. Thus, for example, the axes of the tamping heads may be arranged parallel to each other with the leading edges straight and inclined toward each other or curved inwardly toward each other forming, for example, a semicircle or portion thereof. Alternately, the axes of the tamping heads may be inclined with respect to each other so that the same will intersect in a forward direction and the leading edges of the tamping heads may be perpendicularor substantially perpendicular to these axes.

The driving means for alternately driving the heads in a forward direction may comprise any conventional or known drive means and may, for example, be advantageously in the form of a piston and cylinder for each head with the pistons being alternately driven forward, as for example, pneumatically against the heads in the manner of an impact hammer.

Referring to the embodiment shown in the drawing, as shown in FIGURES 1-3, the power-driven tamping tool consists of a pair of tamping heads 4 and 4a mounted side-by-side with their axes substantially parallel for limited reciprocating movement in a forward and rearward direction with respect to the double cylinder arrange ment 5. The double cylinder arrangement 5 has a compressed air connection 6 and manual holding means 7 by which the device may be manually held and manipulated. In place of the handle 7, the device can, of course, be held by any other known arrangement as, for example, by a strut supported on a rearwardly positioned railroad tie or on a railroad car or the like.

As may be noted from FIGURE 3, the tamping heads 4 and 4a have the leading edges 9 and 9a respectively which actually exert the tamping force on the ballast. These leading edges are curved inwardly toward each other forming, when the heads pass each other in registry, an arc of a circle. Alternately, as shown in FIGURE '5, the leading edges 9 and 9a may be straight and inclined toward each other.

The tamping heads 4 and 4a are screwed into the shank pieces 10 and 10a respectively so that the same may be removed and exchanged for other tamping heads for maintenance and repair purposes. The shanks 1G and 10a have the collars 16 and 16a respectively and the rearwardly extending cylindrical portions 15 and 15a respectively which fit into corresponding cylindrical bores provided with the bearing sleeves 18 and 18a. The inward motion of the shanks 15 is limited by the collars 16 and 16a striking the bearing sleeves and outer rim of the cylinder arrangement. With the shanks 10 in their innermost position, as shown by the shank member Illa with the sleeve striking the cylinder, a striking portion 17 extends into the interior of the cylinder past the bearing sleeve. Within the double cylinder 5 are the cylinder chambers 12 and 12a in which the pistons 11 and 11a respectively freely move axially back and forth. The pistons may be driven in any known or conventional manner as, for example, with each piston being driven pneumatically in the manner of a piston of a pneumatic hammer, but with the pistons 11 and 11a being driven alternately with respect to each other.

In operation the device is positioned as shown in FIG- URE 1 with the tamping heads 9 and 9a extending against the crushed rock ballast 1 beneath the railroad ties 2 of the railroad track 3. The device is maintained in position with an operator holding the handle portion 7 and a compressed air hose is connected to the connection 6. As compressedair is passed through the connection 6 into the device, as for example by opening a valve controlled by the operator, the compressed air drives the piston 11 forward so that the same strikes the striking end 17 of the shank 10 driving the leading edge of the tamping head against the ballast. The downward weight of the upper portion on the tamping head and shank member prevents the same from being driven completely out of the cylinder sleeve 18. The resilient force of the striking or a positive drive such as pneumatic force or spring causes the piston 12 to then retract. The weight of the upper portion of the device on the now extended shank 10 and connected tamping head 4 causes the same to start to retract into the sleeve arrangement 18. At the same time the piston 11a is pneumatically driven forward so as the shank member 10 retracts, the shank member 10a is driven forward with the connected tamping head 4a by the piston 11a striking the striking end 17a. The operation is repeated in continuous, rapid sequence.

Due to the shape of the leading edges 9 and 9a of the tamping heads, the ballast material is compacted forward in the direction of the blow and at the same time moved laterally in the direction toward the other tamping tool. With the use of the tamping heads for example as shown in FIGURE 5, as the head 4 is driven forward, the material is pressed forward in the direction indicated by the arrow 14 in FIGURE 5a. Upon the next stroke, the ballast material is pressed forward by the tamping. head 4a in the direction of the force vector 13 in FIGURE 5a. These force vectors have the forward and lateral components, as shown on the force diagram in FIGURE 5a and upon the pressing forward of the ballast material, by one 40 of the tamping heads, the other head opposes any tendency of the material to escape laterally so that there is obtained a compacting which is considerably better than that obtained with the prior known devices.

Within the broad scope of the invention, the leading edges of the tamping heads may be substantially parallel to each other though the same are preferably shaped as described above.

While the invention has been described in detail with reference to the specific embodiments shown, various changes and modifications will become apparent to the skilled artisan which fall within the spirit of the invention and the scope of the appended claims.

I claim:

1. A power driven tamping tool for compacting ballast under railroad ties comprising at least two adjacent substantially parallel tamping heads mounted side-by-side for limited reciprocating motion in a forward and rearward direction, and means for alternately driving said heads in a forward direction, each said tamping head having its leading edge shaped so that upon forward motion thereof it tends to force material in a lateral direction toward the other tamping head.

2. A tamping tool according to claim 1, in which said tamping heads have leading edges inclined toward each other.

3. A tamping tool according to claim 1, in which said tamping heads have leading edges curved inwardly toward each other.

References Cited in the file of this patent UNITED STATES PATENTS 759,359 Ferguson May 10, 1904 959,530 Hilpert May 31, 1910 1,415,193 Robinson May 9, 1922 1,747,939 Jackson Feb. 18, 1930 1,779,473 Jackson Oct. 28, 1930 2,482,111 Jackson Sept. 20, 1949 2,690,135 Jackson Sept. 28, 1954 FOREIGN PATENTS 449,770 Italy June 30, 1949 

1. A POWER DRIVEN TAMPING TOOL FOR COMPACTING BALLAST UNDER RAILROAD TIES COMPRISING AT LEAST TWO ADJACENT SUBSTANTIALLY PARALLEL TAMPING HEADS MOUNTED SIDE-BY-SIDE FOR LIMITED RECIPROCATING MOTION IN A FORWARD AND REARWARD DIRECTION, AND MEANS FOR ALTERNATELY DRIVING SAID HEADS IN A FORWARD DIRECTION, EACH SAID TAMPING HEAD HAVING ITS LEADING EDGE SHAPED SO THAT UPON FORWARD MOTION THEREOF IT TENDS TO FORCE MATERIAL IN A LATERAL DIRECTION TOWARD THE OTHER TAMPING HEAD. 